Aircraft: WIDEBODY; LOW WING; 3 TURBOJET ENG
Phase of flight: Climb
Anomaly: Aircraft Equipment Problem Less Severe; Inflight Event / Encounter Object; Inflight Event / Encounter Weather / Turbulence

Normal preflight was completed as well as a thorough brief of the departure; EO (Engine Out) SID; and threats for the departure. The main one being the high terrain in all quadrants. The Captain did an outstanding job of setting up and briefing all the appropriate items for the departure and known threats.Normal taxi and takeoff was made on runway 15. We performed an NADP (Noise Abatement Departure Procedure) departure as a precaution and to mitigate the high terrain and performance. As the airport briefing states; a min radius departure was performed and strict adherence to the assigned departure procedure. Because of airspace speed restrictions; and min radius turn requirements we remained configured with SLATS extended and a lower than normal speed.The departure is a quick 180 degree turn to the north. Once we were rolling out on the northwesterly heading; we were confronted with the radar indicating heavy precip directly off our nose and 5 miles or less. This was completely unanticipated. The cell indicated mostly red and took up the entire field of view at the 5 mile range. There was some scalloping and a possible area of less intensity to our right (Northeast). We request and received clearance to deviate and the Captain deviated to the area that looked less intense.Simultaneously; I selected INDENT/GCS (ground clutter suppression) on the radar and verified its tilt to about 5 deg up. I did this to try and isolate the weather from the high terrain. There was very little change; so we knew that this was true weather returns. Being constrained by the terrain; which up until this very instant was the highest threat that we were expecting. We were still in the climb at 250 kts (still less than 10;000 AGL) at around 16;000 ft. Almost right away we entered very heavy precip and what was thought to be an area of less intensity; changed to purple on the radar.The Captain turned back to the left to avoid the purple return; where we encountered extreme precip. This lasted less than 20-30 seconds at the most. Then the precip lessened considerably and in a few more seconds we popped out to nearly clear skies. At some point during this event we leveled at our assigned altitude of 18;000 ft; still maintaining 250 kts; with the landing lights extended (still below 10;000 AGL). We received a climb to I believe FL230 and at 18;500 ft; the landing lights were retracted and the rest of the flight was uneventful.When blocking in; I exited the airplane and the local maintenance person asked what had happened to the landing lights. That's when I saw that the landing lights were broken out. I immediately notified the Captain that we had some damage from what was probably hail. Since we did not have cell phone coverage and SAT phone is not installed we had to get back to the office to call the duty officer; while the maintenance personnel assessed the aircraft and changed the landing lights. The maintenance person's initial impression was that the damage was fairly minor and we would most likely continue the flight after they fixed the lights; called [maintenance control] and cleared the aircraft. So we went back to the aircraft and began a normal preflight and prep to continue. At some point the MX personnel told us that the pictures had been sent to [maintenance control] and that we were waiting to hear back from them. [Report narrative contained no additional information.] Air carrier flight crew encountered unknown severe weather shortly after takeoff from MMTO resulting in possible hail damage.